Dr RK Pachauri, chairman of the Intergovernmental Panel on Climate Change, said the former president signed up to the Kyoto deal to cut emissions, then did nothing to persuade the senate, congress or the public that a cut should be made. He warned that the nations who have ratified the protocol would face similar problems in agreeing the next phase of emissions cuts scheduled for 2005 because the global public are nowhere near ready to agree the changes that would be needed to stabilise the climate.

But he blamed scientists, not politicians, for failing to inspire public concern. Dr Pachauri is an economist. His predecessor in the world's top climate post - an eminent scientist - was supplanted after the Bush administration complained he was too critical of politicians.

The world's top climate scientists in the IPCC have been saying for several years that emissions cuts of 60 per cent and more in developed countries would eventually be needed to allow developing countries an equitable share of economic growth. But Dr Pachauri said that it was not the role of the IPCC to recommend any specific reduction in emissions. His organisation would set out scenarios of future climate trends and leave the world's public to decide on what level of climate change was acceptable.

In his official role he warned of the environmental consequences if the Indian public were to aspire to a car-dominated California-type lifestyle. On a personal level he did express the view that developed countries "could do more". He said the next IPCC assessment report would carry more detailed regional economic analysis to help people reach their decisions. One scenario sees a resulting 11 per cent fall in world GDP, but another suggests that the economy might be only slightly affected.

This has lent weight to the argument - particularly in the USA - that it would be better to risk the climate than to make emissions cuts that might damage the economy. But Dr Pachaudri pointed out that the some small nations would suffer much more than others, with small island states potentially being obliterated by sea level rise.